What happened
On September 6, 2013, at approximately 12:35 UTC, a Nimbus-2C glider crashed in the Speiereck area near St. Michael, Salzburg. The pilot had departed from Unterwössen, Germany, earlier that morning for a cross-country flight, utilizing local weather conditions to guide the route. Upon reaching the Mauterndorf area, the pilot intended to perform ridge soaring along the Speiereck crest.
While attempting to turn away from the ridge to the west, the aircraft's right wing struck trees. The impact caused the glider to strike the rising terrain at approximately 90 km/h. The aircraft slid down a steep slope before coming to a halt after the trailing edges of the wings became entangled in tree trunks. The pilot sustained minor injuries, but the aircraft was destroyed.
The investigation
The Austrian Federal Safety Investigation Board (SUB) examined the flight path using pilot statements, witness accounts from hikers, and data from two flight recorders. The investigation also reviewed the aircraft's maintenance records and the pilot's flight experience. Investigators analyzed the impact marks on the trees, which indicated the aircraft was in a left bank of approximately 25 degrees and a horizontal flight attitude at the moment of collision. The investigation also confirmed that the aircraft was properly registered and maintained, and that the pilot's medical and flight qualifications were valid.
Findings
- The primary cause of the accident was a collision with obstacles in forested, alpine terrain.
- A significant contributing factor was the pilot's low altitude over the ground during ridge soaring.
- The pilot misjudged the required altitude or the distance to the obstacles while maneuvering near the ridge.
- The aircraft was not equipped with an Emergency Locator Transmitter (ELT), which is required for flights in Austrian airspace.
- There were no signs of mechanical failure, pilot health issues, or exceeding weight limits.